YT is just a dying platform. You can even see fandoms start to prioritize Spotify & Apple Music over YT due to multiple factors such as them deleting views. Add on the fact that companies can just pay their way into a seemingly impressive 24 hr view record now and yeah it's no wonder why no one seems to care about them now.
YouTube isn't a dying platform just because it doesn't provide accurate viewing numbers for music videos. Most YT users don't even care about that, because they aren't Kpop fans wanting to boast about how many times they can watch an MV. If YouTube dies, it will be because of its absurdly restrictive rules about what you can and can't do if you want to stay monetized, since no one makes videos just for the sake of it any more. They want to get paid.
That said, as someone mentioned previously, YT will not be replaced by a Chinese app like TikTok. We would never allow that, and we even nearly banned TikTok here several years ago. Not to mention the app would have to be entirely overhauled in order to function like YT. Which begs the question, can anyone even create a replacement for YT without being sued for copying their idea? This is what leads me to believe YouTube won't be replaced by a competitor any time soon, no matter how poorly managed it is.